Hydrangea plant named ‘H212910’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘H212910’, characterized by its upright and somewhat outwardly spreading plant habit; vigorous growth habit; freely branching habit; strong and sturdy stems; freely and uniformly flowering habit; does not require a cold temperature treatment for flower initiation and development; mophead-type inflorescences with numerous red purple-colored sterile flowers with lighter-colored centers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H212910’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a mophead-type Hydrangea and hereinafter referred to by the name ‘H212910’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in De Kwakel, The Netherlands. The objective of the breeding program was to create new freely-branching Hydrangea plants with strong sturdy stems, large inflorescences, attractive flower color and good postproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by the Inventor in April, 2007 in De Kwakel, The Netherlands, of a proprietary selection of Hydrangea macrophylla identified as code number 01-0215-010, not patented, as the female, or seed, parent with a proprietary selection of Hydrangea macrophylla identified as code number 01-0186-046, not patented, as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination in a controlled greenhouse environment in De Kwakel, The Netherlands in March, 2009.

Asexual reproduction of the new Hydrangea plant by vegetative cuttings in a controlled environment in De Kwakel, The Netherlands since June, 2009 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘H212910’. These characteristics in combination distinguish ‘H212910’ as a new and distinct Hydrangea plant:

-   -   1. Upright and somewhat outwardly spreading plant habit.     -   2. Vigorous growth habit; freely branching habit.     -   3. Strong and sturdy stems.     -   4. Freely and uniformly flowering habit; does not require cold         temperature treatment for flower initiation and development.     -   5. Mophead-type inflorescences with numerous red purple-colored         sterile flowers with lighter-colored centers.     -   6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the female parent selection. Plants of the new Hydrangea differ primarily from plants of the female parent selection in sterile flower sepal color as plants of the female parent selection have lighter-colored sterile flowers.

Plants of the new Hydrangea can be compared to plants of the male parent selection. Plants of the new Hydrangea differ primarily from plants of the male parent selection in branching habit and panicle size as plants of the new Hydrangea are more freely-branching and have larger inflorescences than plants of the male parent selection.

Plants of the new Hydrangea can be compared to plants of the Hydrangea hybrida ‘Agrihydrazestien’, disclosed in U.S. Plant Pat. No. 23,841. In side-by-side comparisons conducted in De Kwakel, The Netherlands, plants of the new Hydrangea differed from plants of ‘Agrihydrazestien’ in the following characteristics:

-   -   1. Plants of the new Hydrangea were more freely branching than         plants of ‘Agrihydrazestien’.     -   2. Plants of the new Hydrangea had narrower leaves than plants         of ‘Agrihydrazestien’.     -   3. Plants of the new Hydrangea did not require a cold         temperature treatment for flower initiation and development         whereas plants of ‘Agrihydrazestien’ required a cold temperature         treatment for flower initiation and development.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph is a close-up view of a typical flowering plant of ‘H212910’.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photograph and in the following description were grown during the spring and early summer in 13-cm containers in a glass-covered greenhouse in De Kwakel, The Netherlands and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day and night temperatures averaged 17° C. Plants of the new Hydrangea were pinched one time and were one year old when the photograph and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘H212910’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 01-0215-010, not             patented.         -   Male, or pollen, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 01-0186-046, not             patented. -   Propagation:     -   -   Type cutting.—By vegetative cuttings.         -   Time to initiate roots, summer.—About two weeks at             temperatures about 23° C.         -   Time to initiate roots, winter.—About 18 days at             temperatures about 18° C.         -   Time to produce a rooted young plant, summer.—About four             weeks at temperatures about 23° C.         -   Time to produce a rooted young plant, winter.—About five             weeks at temperatures about 18° C.         -   Root description.—Thick; whitish brown in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant and growth habit.—Upright and somewhat outwardly             spreading plant habit; rounded in shape; strong and sturdy             stems; rapid growth rate and vigorous growth habit.         -   Plant height.—About 30 cm to 35 cm.         -   Plant diameter or area of spread.—About 40 cm. -   Lateral branch description:     -   -   Branching habit.—Freely branching habit with about eight             lateral branches per plant.         -   Length.—About 18 cm to 22 cm.         -   Diameter.—About 4 mm to 5 mm.         -   Internode length.—About 3 cm to 5 cm.         -   Stem texture.—Smooth, glabrous; fully developed, bark-like.         -   Strength.—Strong, sturdy.         -   Color, immature.—Close to 146D, overlain with close to 187C;             lenticels, close to 187C.         -   Color, mature.—Close to 146D, overlain with close to 187C;             lenticels, close to 187C; fully developed, close to 177C. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 7.5 cm to 8.5 cm.         -   Width.—About 6 cm.         -   Shape.—Ovate.         -   Apex.—Acute.         -   Base.—Obtuse.         -   Margin.—Dentate to serrate.         -   Texture, upper surface.—Smooth to rugose, glabrous.         -   Texture, lower surface.—Rugose, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing and fully developed leaves, upper surface:             Close to 147B; venation, close to 145C. Developing and fully             developed leaves, lower surface: Close to 137D; venation,             close to 145D.         -   Petioles.—Length: About 2 cm. Diameter: About 3 mm. Texture,             upper and lower surfaces: Smooth, glabrous. Color, upper             surface: Close to 145B. Color, lower surface: Close to 145C. -   Flower description:     -   -   Flower type and habit.—Showy sterile flowers and small,             inconspicuous star-shaped fertile flowers arranged on             mophead-type terminal panicles; panicles globular in shape;             flowers face upright to slightly outwardly.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants begin flowering about one             year after planting; short production time as a cooling             treatment is not required for flower development; continuous             flowering during the late spring and summer in Northern             Europe.         -   Flower longevity.—Sterile flowers last about four months on             the plant, sterile flowers persistent; fertile flowers last             about one month on the plant, fertile flowers not             persistent.         -   Quantity of flowers.—Freely flowering habit; about 60 to 70             sterile flowers per panicle and about 25 to 30 fertile             flowers per panicle.         -   Panicle height.—About 6.5 cm to 8 cm.         -   Panicle diameter.—About 13 cm to 15 cm.         -   Sterile flower buds.—Length: About 2 mm. Diameter: About             2 mm. Shape: Spherical. Color: Close to 145C.         -   Fertile flower buds.—Length: About 3 mm. Diameter: About             3 mm. Shape: Spherical. Color: Close to 145C.         -   Sterile flower diameter.—About 3.5 cm to 4.5 cm.         -   Sterile flower depth (height).—About 1 cm.         -   Fertile flower diameter.—About 6 mm.         -   Fertile flower depth (height).—About 6 mm.         -   Petals, fertile flowers only, sterile flowers without             petals.—Quantity and arrangement: Five in a single whorl.             Length: About 3 mm. Width: About 2.5 mm. Shape: Ovate. Apex:             Acute. Base: Cuneate. Margin: Entire. Texture, upper and             lower surfaces: Smooth, glabrous. Color: When opening, upper             and lower surfaces: Close to 145D. Fully opened, upper and             lower surfaces: Close to 155B; color does not change with             development.         -   Sepals, sterile flowers.—Quantity and arrangement: Four in a             single whorl. Length: About 2 cm to 2.5 cm. Width: About 2             cm to 2.5 cm. Shape: Deltoid. Apex: Acute to obtuse. Base:             Cuneate. Margin: Entire. Texture, upper surface: Smooth,             glabrous. Texture, lower surface: Smooth to rugose,             glabrous. Color: When opening, upper and lower surfaces:             Close to 144C; towards the base, close to 157D. Fully             opened, upper surface: Close to 67B; towards the base, close             to 73B; color does not change with development. Fully             opened, lower surface: Close to 68D; towards the base, close             to 73B; color does not change with development.         -   Sepals, fertile flowers.—Quantity and arrangement: Five in a             single whorl. Length: About 1.5 mm. Width: About 1.5 mm.             Shape: Ovate. Apex: Acute. Base: Obtuse. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color:             When opening, upper and lower surfaces: Close to 145B. Fully             opened, upper and lower surfaces: Close to 145B; color does             not change with development.         -   Pedicels, sterile flowers.—Length: About 1.5 cm. Diameter:             About 2 mm. Strength: Strong. Texture: Smooth, glabrous.             Color: Close to 145C.         -   Pedicels, fertile flowers.—Length: About 5 mm to 10 mm.             Diameter: About 1 mm. Strength: Strong. Texture: Smooth,             glabrous. Color: Close to 145D.         -   Reproductive organs, fertile flowers only; sterile flowers             without reproductive organs.—Stamens: Quantity per flower:             Eight. Filament length: About 1 mm. Filament color: Close to             155D. Anther shape: Conical. Anther length: About 1 mm.             Anther color: Close to 145D. Pollen amount: Abundant. Pollen             color: Close to 155D. Pistils: Pistil quantity per flower:             Three. Pistil length: About 3 mm. Stigma shape: Oval. Stigma             color: Close to 155D. Style length: About 1 mm. Style color:             Close to 155D. Ovary color: Close to 145C.         -   Seeds.—Quantity per flower: About 20 to 30. Length: About             0.5 mm. Diameter: About 0.1 mm. Color: Close to 200C. -   Disease & pest resistance: Under commercial production conditions,     plants of the new Hydrangea have not been observed to be resistant     to pathogens and pests common to Hydrangea plants. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about 3° C. to about 38°     C. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘H212910’ as illustrated and described. 